Combustion product detecting devices, presently available, are powered directly by an AC or DC energy source or by an AC source whose energy is converted to a DC output for use by the device. In the case of DC powered detectors, a battery normally provides the DC energy. The battery output voltage which is required for proper operation of the detector is relatively high, generally in the range of 9 VDC. Typically, the cost of a DC battery is directly proportional to the output battery voltage desired, that is to say, as the battery output voltage decreases the cost of the battery decreases also. Consequently, cost savings can be achieved by powering a combustion products detector or other battery powered device with a battery having a relatively low voltage output.
However, in attempting to reduce the battery output voltage, difficulties arise since sufficient voltage and current must be provided to assure proper operation of the detector. Furthermore, in an alarm state when the detector senses combustion products present in the region being monitored, sufficient current must be available for the load, including a perceptible indicator, so that the presence of combustion products is satisfactorily made known. On the other hand, the current to the load, in a normal state when the combustion products are not present, should be sufficiently low to minimize the current drain on the energy source. Accordingly, a combustion products detection apparatus is provided as described herein which reduces the amount of energy required for proper operation.